What limits the GVW of a 2500 to 8,800 lbs?

[EarthRoamer]

In Issue 31 of the TDR, page 116, Mr. Perrine a Sr. Manager of Power Train Planning at DamilerChrysler questions my conclusion that the main difference between 2500 and 3500 max GVW ratings is the tires and wheels. #ad


I stand by my original conclusion, and would be interested in any insight or clarifications readers can offer.

Dodge rates its 2500 HD trucks at a maximum GVW of 8,800 lbs. but the 3500 model is rated at 10,500 lbs. So why is the dually GVW rated 1,800 lbs. higher? Is it the frame, springs, brakes, axles, wheels, tires or some combination of these?

I believe the 1,800 lb. difference in GVWs can be mostly (if not entirely) attributed to the load rating of the factory tires and wheels.

According my 1998 Dodge Ram brochure:

a) “Massive, high-strength, 36,000-psi steel frame has a boxed front cross-member and a 9. 5 inch section on the 2500 HD/3500 models for extra stiffness and strength. ”

The 2500 HD and 3500 Rams use the same frame. Both 2500 and 3500 Chassis Cab models use a heavier 11 inch frame, but the 2500 Chassis cab is still rated at a max GVW of 8,800 lbs. but the 3500 Chassis Cab gets a max GVW rating of 11,000 lbs.

b) “Long, 60-inch rear-leaf springs allow for a smoother ride, loaded or unloaded. On Ram 3500 Chassis Cab models, heavy duty auxiliary springs and a rear stabilizer bar are standard (optional on 2500 HD and 3500 pickup models)”

If you get the camper package on the 2500 or 3500, you get the same springs as the 3500 Chassis Cab rated at 11,000 lbs.

c) Front axle rated at 4,500 lbs. for both 2500 HD and 3500 4x2 trucks including Chassis Cab models.
Front axle rated at 4,850 lbs. for both 2500 HD and 3500 4x4 trucks including Chassis Cab models.

The front axles are the same for 2500 HD and 3500 Rams.

d) Rear axle rated at 7,500 lbs. for both diesel and V10 2500 HD and 3500 trucks. The 3500 Chassis Cab is rated at 8,000 lbs.

The rear axles are the same for diesel and V10 2500 HD and 3500 Rams.

e) According to this link: http://www.media. chrysler.com/wwwprkt/258a.htm

The front brakes on the 2500 HD and 3500 trucks are the same 12. 5 x 1. 5 (318 x 38) Vented Discs.

The 2500 HD has 13. 0 x 2. 5 (330 x 63. 5) drum w/ABS for a total swept area of 676. 4 sq. in. (4364 sq. cm. ) but the 3500 HD has 13. 0 x 3. 5 (330 x 89) drum w/ABS for a total swept area of 761. 8 sq. in. (4915 sq. cm. )

The rear brakes on the 3500 are wider by 1 inch resulting in a 11% larger swept area. Depending on the 2500 version, the GCWR (gross combination rating) ranges from 14,000 lbs. to 20,000 lbs. with no mention of trailer brakes, so the 2500 brakes should easily handle a GVW of 10,500 lbs.


So what’s the bottom line? If you convert an 8,800 lb. GVW 2500 HD diesel Dodge Ram to dual rear wheels, you will have the same truck as a Dodge Ram 3500 rated at 10,500 lbs. (Just be sure you have the Auxiliary Rear Suspension Group--Overload springs and rear sway bar).

My conclusion: Replace the factory tires and wheels on the diesel 2500 HD with tires and wheels with a higher rating, and the 2500 HD will be safe up to at least a GVW of 10,500 lbs.

The stock brakes in my opinion leave a lot to be desired, so add a good engine brake and replace the factory brake pads with Performance Friction brake pads.

Do I expect anyone at DaimlerChrystler to give me a green light to load my highly modified 2500 Ram to 10,000 lbs. ? No, I think they're much to smart to risk the potential liability of telling anyone that a 2500 Ram can carry more than 8,800 lbs.

But, we've all seen that Ram on the TV commercial pushing that glacier around. Hmmm. Maybe the Dodge Marketing people should be give Mr. Perrine a call... I think pushing a glacier around MAY exceed the factory specs! #ad



-Bill Swails-
-- email address removed --
EarthRoamer.com
#ad



[This message has been edited by EarthRoamer (edited 02-14-2001). ]

 

[CUMINNTSTRKN]

here's another ? the new hd's from gm rate their 2500 at 9200#. what is the difference? a buddy of mine has a 1984 chevy srw 1 ton that is rated at 9200#. he has thesame size tires that i have, so why the higher rating.

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2001 eth ez box and more on the way

 

[mopars1]

Bill, I agree with you all the way. The only difference is the added two tires/wheels. My 2500 has Michelin LTX A/S LT265/75R16's and they are E rated tires. The sidewall of the tires state that the max weight is 3415lbs for a single tire and 3085lbs when used in a dual tire setup. So adding the two tires on my srw truck would be a max load of 6830lbs. If I were to add two more wheels/tires the max weight for the drw truck would be 12340lbs. Quite a bit of difference.

 

[fallbrookjeff]

I don't know the answer to the following questions, but someone out there might….

Are the springs, shackles and mounting hardware identical between the 2500 & 3500? Are the brakes (pad surface area, drum size, shoe size, size & weight of calipers, wheel cylinder & master cylinder) all identical on the 2500 & 3500?

IF not, these items are important to consider pertaining to GVW. (In my humble option. )

 

[Crazy Horse]

One of the points I was making is that modified syspension or not you will not have the side to side stability with SRW's as DRW's,nomatter what you do. I am well aware also of rolling resistance and width limitations under offroad conditions,I think we're talking about all around road use. I have had my camper on SRW one tons with air bags and mtn. road driving was spooky. Besides with your center of gravity you're not going to do any serious offroading anyway unless you want to be belly up.

[This message has been edited by Crazy Horse (edited 02-15-2001). ]

 

[pcorssmit]

Bill, I'm not quite sure how you're coming up with your numbers for the rear brake swept area.

Here's what I'm getting:

2500:
13" * pi * 2. 5" * 2 sides = 204. 2 sq. in.

3500:
13" * pi * 3. 5" * 2 sides = 285. 9 sq. in.

285. 9/204. 2 = 1. 40 (=3. 5/2. 5), which means the 3500 has 40% more swept area.

BTW, nice lookin' truck.

Pete

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'97 2500 CC 4X4 5spd Sport
'83 K5 Blazer 350 TBI (ex 6. 2), 39. 5 TSLs, 3" lift, Dana 60/GM 14 blt, Detroits

 

[Thomas]

"Total" swept area—looks as though Bill is considering front and rear, not just rear.

 

[EarthRoamer]

>>Bill, I'm not quite sure how you're coming up with your numbers for the rear brake swept area. <<

Ah, I cheated and copied the numbers from the Dodge Media web page. The swept area number I posted is the total for both front and rear brakes.

Pete, you're correct, the 3500 has a 40% larger rear brake swept area than the 2500. The front disc's are the same.

In my opinion, brakes are a weak link in my truck, and I hope to upgrade to the new rear Dodge disc brakes soon.


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Bill Swails
EarthRoamer.com

 

[pcorssmit]

Ahh, I see.

I did a "you can't afford it" rear disk conversion on my Blazer, cost around $150, stops like a champ. Let me know if you want any info. Been wonderin' if'n it'd work on a Dodge. (I think it would. )

Pete

 

[pcorssmit]

Bill, give this a shot. If you have any more questions, post them or call me (check your email for #).
https://www.turbodieselregister.com/ubb//Forum4/HTML/003927.html

Pete

 

[Todd T]

there also is a weight in there that once you cross it, the vehicle has to be equiped with clearance lights and marker lights designating the outermost corners and leading edges of the vehicle. and colored to differenciate front and back of vehicle.



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Todd,
2001 Q-cab SB 4x4 5spd 3. 55's, A pillar Boost/EGT,Jardines 4" turboback kit, and more to come...

 

[Shelby Griggs]

Originally posted by Todd T:
there also is a weight in there that once you cross it, the vehicle has to be equiped with clearance lights and marker lights designating the outermost corners and leading edges of the vehicle. and colored to differenciate front and back of vehicle.

It is not the weight, but the width. Over 80 inches. That is why the 3500's come stock with those lights, they are over the 80 inch DOT number.

Shelby


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2001. 5 2500 QC LB 4WD, ETH (Built 09-10-00), DEE, 3. 54 gears, Laramie SLT, Camper Special, Trailer Tow, Travel Convenience Group, Power Driver Seat, Alarm System, Remote Keyless Entry, Fog Lamps, Cab Clearance Lamps, HD Transfer Case, Bright White with a Gray Interior. Built 09-15-00, took delivery on 10-06-00, 6184 miles as of 02-10-01. Custom aluminum work body / flat bed. Coming soon: E-Brake and gauges.

 

[Crazy Horse]

You will add extra load capacity with 2 more tires on the rear axle but the BIG difference is the stability gained whan you go to DRW's. It's almost spooky driving a single rear wheel truck when you start pushing 10-11,000 lbs. of gross vehicle weight. This is especially true when driving on twisting mountain roads and under windy conditions. I've been there and done that and won't do it again. So far on my current roadtrip my 3500 has come over 13,000 miles weighing 11,820 lbs and towing a 1,700 lb trailer and I can't imagine doing with single rear wheels or any less brakes. You can't compromise safety.

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2K Dodge 3500,4x4,SLT,Quad Cab,PR4 Red,Auto Trans,3. 54's,Anti-Spin Axle,Trailer TowPack,3 Piece Auto Ventshade Hood Protector,"BEEFED" up Factory Camper Pack(No Airbags),Factory Fogs,Rear Slider,Rancho 9000's,Rhino Spray In Liner,Smitty Built Nerf Bars,Alpine 60x4 Watt CD Player,Lance Cabover Camper,BD Plug n Power,K&N w/Modifed Stock Box,Amsoil 15w40,EGT Guage,And Enjoying The Ride.

2K Dodge 2500 SLT RC LB PB3 Blue
99 Dodge 1500 SLT/Sport RC SB Solor Yellow {Her Truck}

 

[EarthRoamer]

>>It's almost spooky driving a single rear wheel truck when you start pushing 10-11,000 lbs. of gross vehicle weight. This is especially true when driving on twisting mountain roads and under windy conditions. <<

I agree that I wouldn't want to drive a STOCK 2500 loaded to 10,000-11,000 pounds; that would be scary.

The point I'm trying to make is that a 2500 Ram can be modified to safely carry more than the factory max GVW of 8,800 pounds, and that the main thing that needs to be upgraded is tires and wheels. The frame, springs and axles can easily carry the load since the 2500 and 3500 share these components.

I believe it's entirely possible to build a single rear wheel truck that handles quite well with a GVW of 10,000 lbs.

My truck has a rear sway bar, two extra leafs in the rear, Air Lift springs in the rear, dual front shocks, Bilstein shocks all around and Michelin XZL off-road truck tires.

I live in Denver where twisty mountain roads and high winds are common. At a weight of 10,000 lbs, my modified truck feels completely safe with little body roll in corners and negligible effect from cross winds. It takes rough roads very well, and the single rear wheels allow me to travel trails that a dually is simply too wide to travel on. The single rear wheels also perform much better in snow and mud.

I'm sure my truck at 10,000 pounds handles and rides better, and has a larger margin of safety than a stock 2500 loaded to 8,800 pounds.

Don't get me wrong, if I was driving on highways in an unmodified stock truck with 10,000 plus pounds, I would be driving a dually. For rough trail conditions, a single rear wheel, modified 2500 works better for me.



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Bill Swails
EarthRoamer.com

 

[DennyDay]

You are correct on the light requirement, DOT lighting is width, and with a trailer legnth comes into play. . If you are towing a trailer of over 80" width, the tractor (truck) cab must be eqipped with marker lights. Never heard of anyone stopped for thisn but it is bound to happen some day.

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Denny
'99 2500 4X4 White short Q cab to much added to put here

 

[Ted Constantine]

Bill,
FYI, I was pleasently surprised to find the anoying "(but they do make an annoying clunking sound when lightly loaded)" clunking noise that I had on my 98. 5 gasser is not present on my 2001. 5 eth/dee.

I would be interested if anyone can add further insight into the 4 wheel discs. I have them, or so I found out after the fact. It was a nice surprise. Are they identical on the 3500 and 2500?

Ted

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2001. 5 2500, quad cab, 4X4, ETH/DEE, 4. 10 LSD, 255/85 BFG MT, Leer topper, Piaa driving 510's in bumper, Line-X, Stereo= JVC KD-MX3000, MBQuart 6. 5 components in front doors, 6. 5 coax in rear, JL Audio Stealth Box sub in center seat, Fosgate 400a4 and 250a2 amps, DynaMat everywhere

 

[Steve St.Laurent]

Bill the only thing I think you are missing is that since you have an auto you don't have the same axle as the 3500. With an automatic 2500 you get the Dana 70 rear end. With the manual 2500's and all 3500's you get the Dana 80H. That's on the diesels, I don't know about the gassers. Other than that I agree with your findings, I know I don't worry too much about overloading my 2500, with the Dana 80H rear end and the camper package I do have the same drivetrain as a 3500 just without the training wheels #ad
. It's also a beefier drivetrain that what Ford puts on their 350 SRW trucks that are rated to 9,900 lbs. I basically use that as my GVWR and make sure that I stay under the axle GAWR ratings as well.



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-Steve St. Laurent - President of the Great Lakes TDR
'98 QC LB (CMNSPWR), 4x4, ISB, 5sp, 4. 10 LSD, TST Powermax, 275hp RV injectors, Joe Donnelly modifed Sachs Clutch, custom ladder bars, SW fuel pressure gauge, BD exhaust brake, Isspro turbo temp monitor, front Draw-Tite receiver, rear Draw-Tite class V receiver, BFG 285/75R16 AT KO's, (all the common stuff clipped)

 

[EarthRoamer]

Originally posted by Steve St. Laurent:
With an automatic 2500 you get the Dana 70 rear end.

Yea, Steves right on the autos getting Dana 70s.

It's interesting that there is no distinction made between the rear axle weight ratings between autos and manuals in the Ram brochure. 2500 HD with V10s/Cummins are rated at 7,500 pounds--same as 3500 Rams?

Shouldn't the hybrid 70/80 have a higher weight rating than the 70?

Or is the hybrid 70/80 designed for the higher torque and "shock" loads of a manual transmission? A torque converter won't allow a driver to transmit the same loads to the rear axle as a clutch popping manual transmission driver could.



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Bill Swails
EarthRoamer.com

 

[EarthRoamer]

I recieved this question in an email and thought TDR readers might find the question and my response useful. If you have any thoughts or insight, please post!

Thank you for your contribution to "Turbodiesel register" and sharing your
knowledge with others . I am very much interested in this topic . I will be
hauling a 5th wheeler trailer and I do not wish to have a dually . I read
your analysis (attached below ) , I would like to know if you have new
information on this subject since you have written that memo on May 2000 .


I actually just posted this a couple of weeks ago on Feb 14th, I'm, glad you are finding my articles and postings useful.


I appreciate if you could provide your opinion on the following items;
1- Are the rear axle lengths between the wheels (supports) the same ? If
3500 series has a shorter rear axle distance( from one inner rear tire to
other inner rear tire) , it would create smaller moment and results in
lesser bending stress under the same loading condition and for the same
axle diameter. Would you comment on this ?


The axle lengths are the same, the dually configuration uses wheels with a different off-set. According to my Ram Sales Brochure the rear track is as follows:
Rear Track, 2500-68 inches, 3500-68 inches
Rear inside track, 2500-58 inches, 3500-49. 4 inches
Rear outside track, 2500-78 inches, 3500-86. 6 inches

As you can see, the centerline of the 2500 single rear wheel and 3500 dually are the same 68 inches. The 3500 would actually have a longer effective moment arm with the offset wheels, but the wider outside track would obviously make the 3500 more stable in a rollover situation.


2- Is new brake design (all 4-wheel disk brakes ) same for the 2500HD and
3500HD series ?

I don't know for sure, but I suspect they are the same. According to the 2001 Ram Brochure: "Ram 2500 HD and 3500 Pickups have larger braking spaces for improved stopping power while hauling loads. " It goes on to say: "The Electronic Variable Brake Proportioning System on Ram 2500 HD and 3500 models helps balance braking for surer, smoother straight-line stopping. "

In my opinion, the 4 wheel discs and Electronic Variable Brake Proportioning System will be a major benefit for you using a Ram as a tow vehicle. The weight of my truck is fairly constant, so I can set up my suspension and braking for my constant heavy load. You have the challenge of setting your rig up for both heavy and no-load driving. It looks like Dodge has (finally!) fixed the Ram braking issues.


3-My expected loading condition will be : 13,000# fully loaded 5'er ( with
approximate hitch weight 2600# ) , and additional weight in the truck 650#
( 2 person + weight of the hitch + minimum misc. ) . A payload of approx .
3500 lbs. Would you consider this payload unsafe for a Modified 2500HD ?


(here modified means- camper package-rear aux. springs and rear stabilizer
bars - , and upgraded wheels &tires .


First, my liability disclaimer #ad
I'm just a guy with an opinion, and I am not qualified in any way to evaluate the safety of Dodge Rams and their carrying capacity. OK, here's what I think:
You didn't say what configuration of 2500 Ram you are considering, and the payload capacity varies. A 2500 4x2 reg cab, long bed has a listed payload of 3,790 pounds, so even Dodge says this configuration is OK for your 3,500 # load. In a worst case scenario, the 2500 4x4, quad cab long box has a max payload of 2,970 pounds, 530 pounds less than your estimated load. According to Dodge, you would be overloaded by 6%.

My suggestion would be:
1) get the camper spring package
2) upgrade your wheels to either Weld Aluminum or Alcoa forged aluminum wheels (or 19. 5 inch wheels)
3) upgrade your tires to heavy duty truck tires.
4) replace the factory shocks with either Bilstein or Edelbrock IAS performer shocks.
5) add airbags to the rear

The factory camper spring package works well (but they do make an annoying clunking sound when lightly loaded), especially since you need springs that will work well both loaded and unloaded. I prefer forged aluminum wheels for the light weight and strength. If you get the Michelin LTX tires with your truck, they should work fine, but I would switch to a higher load rated tire when they wear out. The factory shocks on my 1998 were horrible, unless things have changed with the new truck, replace the shocks ASAP. I really like my airbags, especially to stiffen up the rear springs when driving on the highway. My philosophy is to set the leaf springs up for the max weight I am carrying, and use the airbags to stiffen things up.


Any additional comment is appreciated . Thank you for your response in
advance .


I think a SRW 2500 will work well for your application. Personally, I would get a four wheel drive truck. The first time you need to pull your 5th wheel in slippery conditions, the 4WD will pay for itself.



------------------
Bill Swails
EarthRoamer.com

 

[Eric_77]

On the brake swept area of the 2500 and the 3500 are the drums the same size? On my 92 they were and the service guy suggested for longer life and more braking to use the one ton brakes they were wider (unsure how much) but then I had exact same brakes and axles as the 350 but with just SRW.

I personally have bought the 3/4 tons for towing becuase they pull more according to Chrysler. Same total GCVW but the truck weighs less in the 2500 configuration.

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Eric Kelcher
92 W250 stock 4spd/auto 3. 54
96 2500 extd SLT cam plate 4spd/auto 3. 54
13. 5k 33'utility trailer 19' Galaxie runabout